Book four in the tragic series about the Sinister-Winterbottom twins, who must solve one wretched mystery after the next, brought to you by #1 New York Times bestselling author KIERSTEN WHITE. The electrifying penultimate adventure finds the Sinister-Winterbottoms at the manor of Mr. Frank and Dr. Stein!
After escaping from Edgarenโt and Dr. Jay, the Sinister-Winterbottoms and their friends arrive at Stein Manor Science Camp. They all work together to distract the friendly teenage camp director so they can explore and look for clues about where their parents might be.
Meanwhile, Theo and Alexander settle on a daring plan. They know exactly where Edgarenโt is going to be: coming for them, and the books. This time, theyโll be ready. This time, theyโll get answers. And this time, they wonโt trust the adult in charge, which is easy enough when itโs enormous, lurking, unfriendly Mr. Frank. But as they get closer to opening the books and their parentsโ histories, an unexpected foe is watching everything they do. . . .
Fake volcanoes! Real sea caves! Strangely modified frogs! Startling betrayal! And a lightning-struck manor! all combine for the electrifying penultimate Sinister Summer adventure.